Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
thanh tap » thanh lap, thanh tay, thanh tam
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
cuc ban » cua ban, cac ban, cuu ban
cam cuc » cam xuc, cham cuu, pham cuc
sach ty » sach tu, sach thu, xach tay
nang ma » tang ma, sang ma, nang cao
van cam » van nam, van lam, van cau
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sach y)) nang ma hoi. hieu van cam cuc ban ((thanh tap) OR (thanh tai)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) nang ma hoi. hieu van cam cuc ban ((thanh tap) OR (thanh tai)) cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach y)) nang ma hoi. hieu van cam cuc ban ((thanh tap) OR (thanh tai)) cua viet*".