Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
van hanh » van thanh, ban hanh, van anh
tru nang » tra nang, tri nang, truc nano
cho hoc » co hoc, khoa hoc
van cac » van cau, van bac, dan cac
van hac » van hoc, van ha, van hai
xuc van » duc van, luc van, vuc van
tu nang » tu nong, tu nano, tu lang
cua cau » cua cac, cua chu, cua cay
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ((tu nang) or (tru nang)) cho hoc. hieu ((van cac) OR (van hac)) xuc van hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ((tu nang) OR (tru nang)) cho hoc. hieu ((van cac) OR (van hac)) xuc van hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ((tu nang) or (tru nang)) cho hoc. hieu ((van cac) OR (van hac)) xuc van hanh vi cua cau*".