Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
cau tren » cu tren, ca tren, cau treo
hanh vai » hanh vi, hanh va, hanh tai
noi khoa » ngoai khoa, hoc khoa, tai khoa
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
so sach » so sanh, bo sach, co sach
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
ky sang » ky nang, ky dang, duy sang
tuc va » thuc va, truc va, tuc xa
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((ky sang) or (ky tang)) noi khoa. hieu ve cam tuc va hanh vai ((cau tren) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((ky sang) OR (ky tang)) noi khoa. hieu ve cam tuc va hanh vai ((cau tren) OR (dau tren)).
• Adding a wildcard symbol may retrieve word variants: so sach ((ky sang) or (ky tang)) noi khoa. hieu ve cam tuc va hanh vai ((cau tren) or (dau tren))*.