His questions is:

what are the differents between flds and lds ,they both seem to teach book of mormon?

Since I could not find an official website for the FLDS church I got this from Winkipedia at http://en.wikipedia.org/wiki/FLDS I am really not too familiar wiht them or their pratices except to say that they still practice poligamy, The LDS Church does not and does excommunicate anyone found practicing it and they are a split off of the LDS church after the death of Joseph Smith:

The FLDS Church, although officially claiming their roots back to John Taylor and the LDS Church^[8], can trace their inception back to a schism from the LDS church after many prominent members in and around the community of Short Creek were excommunicated in the late 1920s and early 1930s. ^[9] After the LDS Church renounced polygamy, many members, especially in the southern Utah region, continued the practice of plural marriage. After the Second Manifesto renouncing polygamy was issued in 1904, the LDS Church began excommunicating those who continued the practice of polygamy or solemnized new plural marriages.

Many prominent men in the LDS Church were excommunicated and would soon organize to become leaders of the Mormon Fundamentalist movement, including Lorin Calvin Woolley, Joseph Leslie Broadbent, John Yeates Barlow, Charles Zitting, Joseph White Musser, LeGrand Wooley, and Louis A. Kelsch, who in 1932 formed an association known as the Council of Friends^[10]. The early years of this Mormon Fundamentalist movement were contentious and saw many differing interpretations and opinions among leaders as to how plural marriage should be practiced. These contentions eventually lead to the subsequent schisms that created the many polygamous organizations that now exist in Utah and the surrounding areas including the FLDS Church, originally led by John Yeates Barlow, the Apostolic United Brethren who trace their roots back to John Wickersham Woolley and Lorin Calvin Woolley, but were founded by Rulon C. Allred (also known as the Allred Group), and the Latter Day Church of Christ originally led by Charles Elden Kingston (also known as the Kingston Clan), ^[11] among others. ^[12]

It is commonly believed by all of these polygamous sects that they, apart from the LDS Church, (with some even claiming intervention directly from the leaders of the LDS church) received revelation commanding that plural marriage should not cease. ^[11] This revelation was purportedly received by many of the leaders and the task of these early leaders of the Fundamentalist organizations was to keep alive the practice of plural marriage and preserve the keys and doctrines of plural marriage on the earth.

The FLDS church has been led by a succession of men whom they believe to be prophets, who were called of God to lead them. This began with John Yeates Barlow who led the community of Short Creek until his death on December 29, 1949. He was succeeded by Joseph White Musser who was the leader during the infamous Short Creek Raid. He led the community until a contentious appointment of Rulon Allred to a high position of authority in 1951 angered members of the Short Creek Community. Musser had appointed Rulon Allred to be his successor, but Allred was not accepted by the Short Creek community as such. This led to yet another schism among the followers, with many breaking off and following Allred to the Apostolic United Brethren, who located in the southern Salt Lake valley and also in Mexico, but the core faithful in the Short Creek area instead followed Charles Zitting as their leader. This can be viewed as the consolidation of the FLDS church as it is known today. Zitting died in 1954 and Leroy S. Johnson was chosen to lead the faithful in Short Creek. Leroy S. Johnson led the FLDS many years until his death in 1986. He was succeeded by Rulon Jeffs, who assumed the position of prophet, a title his predecessor refused to use. In Jeffs' later years, his poor health led to his son, Warren Jeffs serving as leader of the church in his stead, and upon Rulon's death, Warren Jeffs essentially proclaimed himself prophet and leader of the FLDS Church. Warren Jeffs is assumed to still be leading the FLDS church, even though he is currently in the custody of the State of Utah, and on trial for rape as an accomplice, for the alleged forced marriage of a 14 year old girl to her first cousin. There are some reports though that others, unnamed, within the FLDS community have been leading the community in his absence.

For more information on the Church of Jesus Christ of Latter-day Saints go to http://mormon.org

Hope this helps somewhat.

All other input is welcome and appreciated.