Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
hieu va » lieu va, hieu qua
vai cua » dai cua, hai cua, lai cua
xuc van » duc van, luc van, vuc van
cac xuc » cam xuc, cac nuoc, chat xuc
cua cau » cua cac, cua chu, cua cay
hieu ve » hieu van
cuo hoc » co hoc, cho hoc, cao hoc

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 ((tu nano) or (truc nano)) cuo hoc. ((hieu ve) OR (hieu va)) cac xuc van hanh vai cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tu nano) OR (truc nano)) cuo hoc. ((hieu ve) OR (hieu va)) cac xuc van hanh vai cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((tu nano) or (truc nano)) cuo hoc. ((hieu ve) OR (hieu va)) cac xuc van hanh vai cua cau*".