Perhaps you should try some spelling variations:
thanh vai » thanh van, thanh tai, thanh oai
thanh hai » thanh phan, thanh hoa, thanh san
hang hoa » hang khoa, thanh hoa, hang va
su triet » su tien, ve triet
su viet » so viet
thu vat » thuc vat, thu va, thuat vat
hieu ve » hieu va, hieu van
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky hang » ky nang, ly hang, ky dang
sai ky » sac ky
ve nam » he nam, va nam, le nam
tu sai » tu bai, tu san, tu cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sai ky hang hoa hoi. hieu ve nam thu vat ((thanh vai) OR (thanh hai)) ((su triet) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky hang hoa hoi. hieu ve nam thu vat ((thanh vai) OR (thanh hai)) ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky hang hoa hoi. hieu ve nam thu vat ((thanh vai) OR (thanh hai)) ((su triet) or (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu sai ky hang hoa hoi. hieu ve nam thu vat ((thanh vai) OR (thanh hai)) ((su triet) or (su viet))*.