Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
sang mai » sang ma, sang tai, lang mai
hanh vai » hanh vi, hanh va, hanh tai
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau treo
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
van cam » van lam, van cau, van dam
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
xuc va » duc va, tuc va, luc 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 sang mai hoi. hieu ((van cam) or (van nam)) xuc va hanh vai ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang mai hoi. hieu ((van cam) OR (van nam)) xuc va hanh vai ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang mai hoi. hieu ((van cam) or (van nam)) xuc va hanh vai ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang mai hoi. hieu ((van cam) or (van nam)) xuc va hanh vai ((cuu tre) OR (cau tren))*.