Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cua triet, dua tren
hanh di » hanh vi, hanh de, hang di
luc van » luoc van, luu van, duc van
cuu tre » cau tren, cau treo
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
tu sach » su sach, te sach, tu cach
ma hoi » mai hoi, xa hoi, ma hoa
ha luc » ha duc, nhan luc, than luc
van ha » van hoa, van chat, van phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) OR (tu sach)) ky tang ma hoi. hieu van ha luc van hanh di ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (tu sach)) ky tang ma hoi. hieu van ha luc van hanh di ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (tu sach)) ky tang ma hoi. hieu van ha luc van hanh di ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (tu sach)) ky tang ma hoi. hieu van ha luc van hanh di ((cua tre) or (cuu tre))*.