Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
su triet » su viet, su tien, ve triet
may thoi » gay thoi, may thi, tay thoi
thuc va » thuc vat, thuc dan, thuc day
va cham » va chat, va tham
may hoi » tay hoi, mai hoi, may hmi
hieu va » lieu va, hieu qua
ky mang » ky nang, ke mang, ky dang
sac ky » cac ky, sai ky
tai su » tai so, tai tu, lai su
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky mang ((may hoi) OR (may thoi)). hieu va cham ((tuc xa) or (thuc va)) thanh tai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky mang ((may hoi) OR (may thoi)). hieu va cham ((tuc xa) OR (thuc va)) thanh tai su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky mang ((may hoi) OR (may thoi)). hieu va cham ((tuc xa) or (thuc va)) thanh tai su triet".
• Adding a wildcard symbol may retrieve word variants: tu sac ky mang ((may hoi) OR (may thoi)). hieu va cham ((tuc xa) or (thuc va)) thanh tai su triet*.