Perhaps you should try some spelling variations:
sach doi » sach hoi, sach moi, sach dao
doi nang » dai nang, hoi nang, voi nang
hanh tai » thanh tai, hang tai, han tai
su sach » so sach, vu sach
hanh va » hang va, hanh vi
cuu tre » cua tre, cau tren, cau treo
va cham » va chat, va tham
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
xuc va » duc va, luc va, xac va
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: su sach doi nang xa hoi. hieu va cham ((xuc va) OR (tuc va)) ((hanh tai) or (hanh va)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach doi nang xa hoi. hieu va cham ((xuc va) OR (tuc va)) ((hanh tai) OR (hanh va)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach doi nang xa hoi. hieu va cham ((xuc va) OR (tuc va)) ((hanh tai) or (hanh va)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach doi nang xa hoi. hieu va cham ((xuc va) OR (tuc va)) ((hanh tai) or (hanh va)) cuu tre*.