Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cham tuc » nham thuc, pham thuc, tham thuc
lang mai » lang dai, lang hai, lang man
mai khoi » mai khoa, tai khoa, cac khoi
hanh tai » thanh tai, hang tai, han tai
cuu tre » cua tre, cau treo
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
hieu ve » hieu van
ky lang » ky nang, ky dang, ky tang
tuc va » thuc va, truc va, tuc xa

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 lang mai khoi. ((hieu ve) OR (hieu va)) cham tuc va hanh tai ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang mai khoi. ((hieu ve) OR (hieu va)) cham tuc va hanh tai ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang mai khoi. ((hieu ve) OR (hieu va)) cham tuc va hanh tai ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang mai khoi. ((hieu ve) OR (hieu va)) cham tuc va hanh tai ((cuu tre) or (cau tren))*.