Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
qua cham » qua hai, qua cac, va cham
hang vi » hang va, hanh vi, hang di
thuc va » thuc vat, thuc dan, thuc day
tu nang » tru nang, tu nong, tu nano
cuu tre » cua tre, cau tren, cau treo
tuc va » truc va, tuc xa, duc va
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) tu nang x hoi. hieu qua cham ((tuc va) OR (thuc va)) hang vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) tu nang x hoi. hieu qua cham ((tuc va) OR (thuc va)) hang vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) tu nang x hoi. hieu qua cham ((tuc va) OR (thuc va)) hang vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) tu nang x hoi. hieu qua cham ((tuc va) OR (thuc va)) hang vi cuu tre*.