Perhaps you should try some spelling variations:
dua tren » dung tren
va doanh » van doanh, vay doanh, va danh
cham loc » cham soc, chon loc, cham o
tu sach » thu sach, su sach, te sach
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
ty nang » ky nang, ty hang, ly nang
cuu tre » cua tre, cau tren, cau treo
loc va » hoc va, luc va

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 ((ty nang) or (ty xang)) xa hoi. hieu vu cham loc va doanh tai ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty xang)) xa hoi. hieu vu cham loc va doanh tai ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) or (ty xang)) xa hoi. hieu vu cham loc va doanh tai ((dua tren) or (cuu tre))*.