Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
dang ma » dang mau, dang mam, dang mat
hieu va » hieu qua
xuc van » duc van, luc van, vuc van
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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 ky dang ma hoa. ((hieu va) or (lieu va)) cam xuc van hanh dai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky dang ma hoa. ((hieu va) OR (lieu va)) cam xuc van hanh dai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky dang ma hoa. ((hieu va) or (lieu va)) cam xuc van hanh dai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang ma hoa. ((hieu va) or (lieu va)) cam xuc van hanh dai ((cua tre) OR (cuu tre))*.