Perhaps you should try some spelling variations:
su triet » su viet, ve triet
tang tai » hang tai, dung tai, sang tao
tu sach » thu sach, su sach, te sach
va tang » va trang, van tang, ha tang
cao thu » cao thi, cac thu, ca thu
hieu va » lieu va, hieu qua
su tien » su kien, su hien, tu tieng
va cao » va cac, va co, va dao
y nang » ky nang, ly nang, may nang
thu va » thuc va, thue va, tu va
v nang » va nang, vu nang, van nang

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 ((y nang) or (v nang)) xa hoi. hieu va cao thu va tang tai ((su triet) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (v nang)) xa hoi. hieu va cao thu va tang tai ((su triet) OR (su tien)).
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) or (v nang)) xa hoi. hieu va cao thu va tang tai ((su triet) or (su tien))*.