Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
chau tre » chay tren, chau tho, cho tre
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach tu, sach thu
van cam » van nam, van lam, van cau
nang xa » nang x, lang xa, mang xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty ((nang xa) or (nang ma)) hoi. hieu van cam xuc ((van hanh) OR (ban hanh)) lai chau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty ((nang xa) OR (nang ma)) hoi. hieu van cam xuc ((van hanh) OR (ban hanh)) lai chau tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty ((nang xa) or (nang ma)) hoi. hieu van cam xuc ((van hanh) OR (ban hanh)) lai chau tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ty ((nang xa) or (nang ma)) hoi. hieu van cam xuc ((van hanh) OR (ban hanh)) lai chau tre*.