Perhaps you should try some spelling variations:
van giang » manh giang, tran giang, dan gian
giang lai » gianh lai, giang hai, giang lam
thuc van » thuc vat, thuc dan, thuc va
chau tre » chay tren, chau tho, cho tre
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va cham » va chat, va tham
va cam » va cac, va cao, va cai

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 ky nang xa hoi. hieu ((va cam) or (va cham)) thuc van giang lai chau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu ((va cam) OR (va cham)) thuc van giang lai chau tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu ((va cam) or (va cham)) thuc van giang lai chau tre*.