Perhaps you should try some spelling variations:
sach doi » sach hoi, sach moi, sach dao
doi nang » dai nang, hoi nang, voi nang
tu sach » thu sach, su sach, te sach
hanh va » hang va
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
xuc va » duc va, luc va, xac va
ve cam » ve cham, ve cac, va cam
tuc va » thuc va, truc va, tuc xa

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 doi nang xa hoi. hieu ve cam ((xuc va) OR (tuc va)) ((hanh vi) or (hanh va)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi nang xa hoi. hieu ve cam ((xuc va) OR (tuc va)) ((hanh vi) OR (hanh va)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach doi nang xa hoi. hieu ve cam ((xuc va) OR (tuc va)) ((hanh vi) or (hanh va)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach doi nang xa hoi. hieu ve cam ((xuc va) OR (tuc va)) ((hanh vi) or (hanh va)) cuu tre*.