Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien nang » thien bang, thien dang, trien nang
cau tren » cu tren, dau tren, ca tren
cua tre » cua te, cuu tre, cua triet
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
van cam » van lam, van cau, van dam
nang xa » nang x, lang xa, nang ma
xuc va » duc va, tuc va, luc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach thien nang xa hoi. hieu ((van cam) OR (van nam)) xuc va hanh va ((cua tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thien nang xa hoi. hieu ((van cam) OR (van nam)) xuc va hanh va ((cua tre) OR (cau tren))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach thien nang xa hoi. hieu ((van cam) OR (van nam)) xuc va hanh va ((cua tre) or (cau tren))*".