Perhaps you should try some spelling variations:
thanh mau » hanh mau, thanh san, thanh hai
thanh may » thanh tay, hanh may, thanh lay
duc tien » duc thien, luc tieng, thuc tien
nang mat » nang ma, dang mat, nang suat
hieu ve » hieu va, hieu van
cac toc » cac toi, cac nuoc, cac thoi
sach ky » sac ky, sach y, sach ty
mat hoa » ma hoa, mai hoa, chat hoa
duc tre » duoc tren
tu sach » thu sach, su sach, te sach
ve cac » va cac, vien cac
toc va » hoc va, toc ta, tuc va

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 ky nang mat hoa. hieu ve cac toc va ((thanh may) or (thanh mau)) ((duc tre) OR (duc tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang mat hoa. hieu ve cac toc va ((thanh may) OR (thanh mau)) ((duc tre) OR (duc tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang mat hoa. hieu ve cac toc va ((thanh may) or (thanh mau)) ((duc tre) OR (duc tien))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang mat hoa. hieu ve cac toc va ((thanh may) or (thanh mau)) ((duc tre) OR (duc tien))*.