Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cham duc » pham duc, cham soc, pham duy
lang mai » lang dai, lang man, sang mai
hanh tai » thanh tai, hang tai, han tai
lang hai » lang chai, lang thai, lang ha
cuu tre » cua tre, cau treo
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
ve cham » va cham, ve chat, vu cham
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van

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) OR (lang hai)) khoi. hieu ve cham duc 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) OR (lang hai)) khoi. hieu ve cham duc 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) OR (lang hai)) khoi. hieu ve cham duc va hanh tai ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((lang mai) OR (lang hai)) khoi. hieu ve cham duc va hanh tai ((cuu tre) or (cau tren))*.