Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
tai khoi » mai khoi, tao khoi, tai hoi
tai khoa » da khoa, noi khoa
vu sach » vu bach, su sach, vu khach
ky sang » ky nang, ky dang, ky tang
cua tre » cuu tre, cua triet, dua tren
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
cam luc » cam xuc, cau luc
va hanh » van hanh, va thanh, va danh
ve cam » ve cham, ve cac, va cam
luc va » duc va, tuc va, loc va
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky sang ((tai khoi) OR (tai khoa)). hieu ve cam luc va hanh hai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky sang ((tai khoi) OR (tai khoa)). hieu ve cam luc va hanh hai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky sang ((tai khoi) OR (tai khoa)). hieu ve cam luc va hanh hai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: vu sach ky sang ((tai khoi) OR (tai khoa)). hieu ve cam luc va hanh hai ((cua tre) or (cua te))*.