Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
van hanh » van thanh, ban hanh, van anh
doc sach » hoc sach, nuoc sach, dac sac
nano cho » nang cho, nano cuo, nang chon
xuc van » duc van, luc van, vuc van
cac xuc » cam xuc, cac nuoc, chat xuc
hieu ve » hieu va, hieu van
cho hoc » co hoc, khoa hoc
tu nano » truc nano
ve cac » va cac, vien cac
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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