Perhaps you should try some spelling variations:
cua quoc » cua nuoc, cua thuoc
tan hanh » tan thanh, tang hanh, toan hanh
dieu cua » dieu tra
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
doi cua » dai cua, hoi cua
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
ca duc » cao duc, cua duc, ca dua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ky lang xa hoi. hieu qua ((ca duc) or (cua quoc)) tan hanh ((doi cua) or (dieu cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky lang xa hoi. hieu qua ((ca duc) OR (cua quoc)) tan hanh ((doi cua) OR (dieu cua)) viet.
• Adding a wildcard symbol may retrieve word variants: tu san ky lang xa hoi. hieu qua ((ca duc) or (cua quoc)) tan hanh ((doi cua) or (dieu cua)) viet*.