Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
chat xuc » chat huu, cam xuc, chao xu
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
tang ma » tang van
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, sach thu
cac xuc » cam xuc, cac nuoc, cac cuoc
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((tang ma) OR (mang may)) hoi. hieu ve ((cac xuc) or (chat xuc)) van hanh dai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((tang ma) OR (mang may)) hoi. hieu ve ((cac xuc) OR (chat xuc)) van hanh dai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((tang ma) OR (mang may)) hoi. hieu ve ((cac xuc) or (chat xuc)) van hanh dai cua tu".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((tang ma) OR (mang may)) hoi. hieu ve ((cac xuc) or (chat xuc)) van hanh dai cua tu*.