Perhaps you should try some spelling variations:
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
va tinh » may tinh
tinh ca » tinh cao, tinh cua, tinh va
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
tuc va » thuc va, truc va, tuc xa
cua te » cua tu
thiet » thieu

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 nang ((xa hoi) or (mai hoi)). hieu va cac tuc va tinh ca ((cua te) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky nang ((xa hoi) OR (mai hoi)). hieu va cac tuc va tinh ca ((cua te) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: tu san ky nang ((xa hoi) or (mai hoi)). hieu va cac tuc va tinh ca ((cua te) or (va thiet))*.